Mounjaro (tirzepatide) is a prescription drug that helps manage blood sugar levels in certain people with type 2 diabetes. It works by imitating the effects of certain hormones called incretins.

Mounjaro is a type of drug called a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist.

Mounjaro helps manage blood sugar levels in adults and children ages 10 years and older with type 2 diabetes. With this condition, the body doesn’t have a typical response to insulin. (Insulin is a hormone made in your pancreas that helps move sugar from the blood into cells. The cells use insulin as energy.) Eventually, the pancreas creates less insulin.

Mounjaro’s mechanism of action (how it works) is by imitating the effects of hormones called incretins. Specifically, Mounjaro mimics GIP and GLP-1 incretins by activating certain receptors (binding sites) in the body.

By activating these receptors, Mounjaro lowers fasting and post-meal blood sugar levels. The drug does this by:

  • signaling your pancreas to release more insulin after you eat when blood sugar is high
  • making your body extra sensitive to insulin
  • stopping your liver from making additional sugar

Mounjaro also slows the movement of food through your digestive tract, making you feel full for longer than usual.

Mounjaro starts working after your first dose, but it takes time to reach its full effect.

The starting dose of 2.5 milligrams is not meant to lower blood sugar right away. Instead, it helps your body adjust and reduces stomach-related Mounjaro side effects, such as nausea. Your doctor will slowly increase your dose of Mounjaro until they find the amount that’s right for you. They’ll usually increase the dose every 4 weeks.

Your doctor can let you know what to expect during Mounjaro treatment, including how often they’ll monitor your blood sugar and A1C levels. (A1C is a blood test that measures your average blood sugar level over the previous 3 months.)

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